Newport 66
Old Man with a Hat
Thanks again for all of your insight.....
413 Engine
- Thread starter Newport 66
- Start date
twostick
Senior Member
Then a hypereutectic piston will suit your application perfectly. They have a very specific installation procedure as far as piston to wall clearance and ring gap is concerned. They get a bad rap because they are perceived to be brittle and prone to failure but 99% of failures not caused by detonation can be traced back to not enough ring gap and/or too much piston to wall clearance.
Seeing as I'm spending your money and just saved you some on pistons, I would suggest you not use those 906 open chamber heads especially if you want to venture into 10:1 compression territory. They will need a complete rebuild including hardened exhaust seats, new guides and valves and all the associated machine work. At a competent machine shop you just spent $1000 +/- to do that and you will still have an iron open chamber head that will not deal with pump gas very well at your CR. For about the same money +/- you can have a set of 440Source Stealth aluminum closed chamber heads that will allow you to run very well on pump gas and they will flow out of the box as well as all but the most extreme ported iron heads.
I would spend a couple of hours at the machine shop having them checked over and a proper valve job done which should be done no matter who's aftermarket head you might choose.
I would try to choose a piston and rod combo that will put the piston at zero deck with minimal deck machining and run a .039 head gasket for maximum quench. That is the ticket for pump gas and no detonation. I would under no circumstances use the dumptruck rods that are in that engine now. As I said before, a set of new H-beams while not really a necessity for what you are building are not much more $$$ than rebuilding some 50 year old stock ones. The advantages are H-beams are lighter and they are new.
Cam and carb to taste but you should be able to approach 400 HP without requiring anything wilder than a 6Pak type cam, maybe with a little more lift and a stock torque converter or at the most a stock high stall that came in lots of late model Mopars, about 2200 RPM IIRC. A mild cam like that could still use the stamped rocker arms with correct measured length push rods.
Kevin
Stock 360 horse cam or a stock magnum cam probably would suit your needs. You will need to determine if the engine has the heavy rods or not. I would suggest tossing the heavy rods in favor of the after market passenger rods which are a good deal lighter and have stronger bolts and caps. Pistons will need to be mated to the closed chamber heads to get to a 10-1 compression ratio. An alternative to get to a 10-1 compression ratio would be to find a set of the closed chamber heads and have the larger valves installed and run stock 360 horse pistons. If the engine had heavy truck components, you will need to rebalance the crank if you decide to go this route.
Dave
As I recall, the real difference in the 413/340 and 413/360 motor was dual exhausts. A smidgen more cam, but not much. Maybe a smidgen more cfm in the AFB om the 360 motor too? The later 440/375 is quite a bit more cam than either one, duration and lift.
It's my understanding that the 440/390 cam is still the same specs as the 440/375 cam, BUT with more taper on the lobes, laterally, so the lifters will rotate more and better handle the higher valve spring pressures of the 440/390 motor. Which is why that motor has a different cam/lifter package than the 440/375 engine.
For your stated purposes, you might find a "core motor" 440 and get the rods and crank out of it. Then re-sell the remains to somebody who needs to build a 440 and is going to use something similar to a Scat rotating assembly for it. THAT will get you a set of "factory balance" rods, of the lighter weight. Then get the bearing end resized/rebuilt and put new bolts/nuts in at that time. Then, you'll just need to find some pistons of the same weight as the core 440's pistons, which would also decrease the need for a balance job. The added strength of the H-beam rods wouldn't be a necessity for a good-running street motor, I suspect. Granted, the lighter weight and greater strength would be assets in some motors, especially the lighter weight, but if getting them also ups the cost factor due to the required balance job, everything has a price.
When the earlier closed-chanber heads were in use, port size and valve size were important issues in ultimate port flow. When the 906s came online, it was about better combustion chamber dynamics with the "open chamber" (PLUS related emissions issues, at the time). Then the later '72 and later heads were supposed to flow worse due to a flatter intake port. Only thing was . . . when the Mopar Performance Porting Template kit was used to massage the ports, it seems that all THREE heads' ports flowed pretty much the same amount. As flow benches were more available and in more cylinder head repair shops, especially the race-oriented ones. So with that evolving information, it was later learned that the closed chamber head was really better for a more dynamic "active air" combustion chamber (according to David Vizard). It was also learned that low-lift flow, on a street engine, is more important than .500" lift flow, as the cam won't have that much lift in it. Plus, port velocity is an important issue, too! LOTS of things to consider and their related dynamics, too.
Nothing wrong with hypereutectic pistons. I had my Chevy 350 built with some of the first ones, right after they came out. The strength of a forged piston, but runs with the clearance of a cast piston. That was about 250K miles ago. IF you can find some for the 413 with the skirt coating, get them as that coating is an anti-scuff/anti-friction coating.
If you can find the NHRA specs for a 413 car V-8, it'll probably have a related piston manufacturer and part number for the pistons allowed in the stock class for that motor. Might be forged rather than cast, but that's a minor thing, to me.
Just more thoughts,
CBODY67
It's my understanding that the 440/390 cam is still the same specs as the 440/375 cam, BUT with more taper on the lobes, laterally, so the lifters will rotate more and better handle the higher valve spring pressures of the 440/390 motor. Which is why that motor has a different cam/lifter package than the 440/375 engine.
For your stated purposes, you might find a "core motor" 440 and get the rods and crank out of it. Then re-sell the remains to somebody who needs to build a 440 and is going to use something similar to a Scat rotating assembly for it. THAT will get you a set of "factory balance" rods, of the lighter weight. Then get the bearing end resized/rebuilt and put new bolts/nuts in at that time. Then, you'll just need to find some pistons of the same weight as the core 440's pistons, which would also decrease the need for a balance job. The added strength of the H-beam rods wouldn't be a necessity for a good-running street motor, I suspect. Granted, the lighter weight and greater strength would be assets in some motors, especially the lighter weight, but if getting them also ups the cost factor due to the required balance job, everything has a price.
When the earlier closed-chanber heads were in use, port size and valve size were important issues in ultimate port flow. When the 906s came online, it was about better combustion chamber dynamics with the "open chamber" (PLUS related emissions issues, at the time). Then the later '72 and later heads were supposed to flow worse due to a flatter intake port. Only thing was . . . when the Mopar Performance Porting Template kit was used to massage the ports, it seems that all THREE heads' ports flowed pretty much the same amount. As flow benches were more available and in more cylinder head repair shops, especially the race-oriented ones. So with that evolving information, it was later learned that the closed chamber head was really better for a more dynamic "active air" combustion chamber (according to David Vizard). It was also learned that low-lift flow, on a street engine, is more important than .500" lift flow, as the cam won't have that much lift in it. Plus, port velocity is an important issue, too! LOTS of things to consider and their related dynamics, too.
Nothing wrong with hypereutectic pistons. I had my Chevy 350 built with some of the first ones, right after they came out. The strength of a forged piston, but runs with the clearance of a cast piston. That was about 250K miles ago. IF you can find some for the 413 with the skirt coating, get them as that coating is an anti-scuff/anti-friction coating.
If you can find the NHRA specs for a 413 car V-8, it'll probably have a related piston manufacturer and part number for the pistons allowed in the stock class for that motor. Might be forged rather than cast, but that's a minor thing, to me.
Just more thoughts,
CBODY67
The 413, 360 had a better cam 430/430 (lift) than the std 413 at 392/390. The dual quad ram engines ran 444/450 on mechanical lifters. These engines typically ran a 10-1 compression ratio on the various horsepower ratings. The letter series cars and others that had the 360 horse option all had dual exhaust with the old style log manifolds. Dual exhaust could also be had on the lower horse power engines.
The 440 Performance engines ran very similar cams to the older 413/360, but got a boost due to new high performance exhaust manifolds introduced in during the '66 model run. The improved exhaust and more displacement was the primary reason for the increased power of the 440 engines along with better valve springs and larger valves.
Dave
The 440 Performance engines ran very similar cams to the older 413/360, but got a boost due to new high performance exhaust manifolds introduced in during the '66 model run. The improved exhaust and more displacement was the primary reason for the increased power of the 440 engines along with better valve springs and larger valves.
Dave
sprice
Active Member
When this came up locally I did some googling and found same information about 413's being available in trucks until late 70"s. I did not know this. If anybody interested, I can provide information. City of Winnipeg & Vema Equipment | ASSOCIATED AUTO AUCTION LTD
Does it have a 2- or 4-bolt main? If the latter, the block is physically stronger.
Newport 66
Old Man with a Hat
I haven't started disassembly yet. When I do I post some pics and info. More than likely after Thanksgiving since were hosting a large family gathering in the shop!! I'm still trying to get my feeble brain wrapped around all the info you guys have provided. What an outstanding group here. You can all pat yourselves on the back and THANKS for the expertise!!
commando1
Old Man with a Hat
What?
4 bolt Main???
twostick
Senior Member
And not a Mopar. Even a Keith Black block has 2 bolt mains. Stock Hemi blocks are only 2 bolts. The only thing extra on them is cross bolts. Stock Hemi blocks have two cross bolts, the new Black blocks have 4. No stock wedge block that I'm aware of ever had 4 bolt mains.
Kevin
I have never taken one Mopar engine down to parts, so I apologize for the major mistake. Other makes such as Ford had truck blocks with the 4-bolt main and I generalized it stupendously.
Unless you want to do this yourself as a major project....
I recommend getting a crate 440 from Carolina Machine Engines. They build them from the intake down to the oil plug and dyno the engine probably for as much $$$ as you are going to spend on this project. Plus.....they give you a warranty.
www.cmengines.com
I recommend getting a crate 440 from Carolina Machine Engines. They build them from the intake down to the oil plug and dyno the engine probably for as much $$$ as you are going to spend on this project. Plus.....they give you a warranty.
www.cmengines.com
Looks nice!
Newport 66
Old Man with a Hat
Aside from the machine work, I'd do the assembly myself.
Ripinator
Old Man with a Hat
Show off. . .
MoPar Maniac
Well-Known Member
On a related subject when I worked at MODoT we got two new 1975 D600 dump trucks. They has 361 2 barrel engines but they had angle plug heads like the small blocks.
twostick
Senior Member
Newport 66
Old Man with a Hat
Update:
Started the disassembly. So far its it's coming b.c apart pretty well. The drivers side exhaust manifold bolt heads are rusted and eroded, gonna fire up the gas wrench to get them out. Pulled the right head off the cyl. bore looks good. Dished pistons for low(er) compression. Those heads are definitely unique in the RB world!! Stay tuned....
Started the disassembly. So far its it's coming b.c apart pretty well. The drivers side exhaust manifold bolt heads are rusted and eroded, gonna fire up the gas wrench to get them out. Pulled the right head off the cyl. bore looks good. Dished pistons for low(er) compression. Those heads are definitely unique in the RB world!! Stay tuned....
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